This invention relates generally to starburst dendrimers and their preparation from epoxy-functionalized nitroalkanes.
Starburst dendrimers have been known for more than 25 years and find applications in drug delivery, diagnostics, transfection agents, as catalyst supports and more common applications such as viscosifiers. Dendrimers are generally prepared by sequential reactions which incorporate a branching group. Typical branching groups include amine groups and polyols such as pentaerythritol. Typical reactions used to produce the branches are Michael addition reactions of acrylate esters to amines, followed by amidation reactions e.g. PAMAM dendrimers, or ring opening of (poly)epoxides.
The challenge of current dendrimer syntheses is that reaction steps often require the use of a large excess of one of the reagents, or requires the synthesis of multiple monomers, often with elaborate protection group strategies in order to generate the desired monomers. Even when these elaborate monomers are prepared, changing the chemistry to expand the generations is frequently required because the use of a large excess of a complex multifunctional monomer is simply uneconomical.
The problem addressed by this invention is the provision of new dendrimers and processes for making them that overcome one or more shortcomings of the previously known systems.